JP2976960B2 - Stacked three-terminal capacitor array - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer three-terminal capacitor array, and more particularly to a multilayer three-terminal capacitor array in which a plurality of three-terminal capacitors used as a noise filter or the like are formed in one chip.

[0002]

FIG. 9 is a perspective view showing an example of a conventional laminated three-terminal capacitor array. The multilayer three-terminal capacitor array 1 includes a multilayer body 2. The stacked body 2 includes a plurality of dielectric layers 3a to 3d as shown in FIG. On the first dielectric layer 3a, for example, four linear signal electrodes 4
a to 4d are formed. On the second dielectric layer 3b, a ground electrode 5 is formed on almost the entire surface except for both sides where the signal electrodes 4a to 4d are exposed. Further, on the third dielectric layer 3c, other signal electrodes 6a to 6d are formed at positions corresponding to the signal electrodes 4a to 4d. Then, a fourth dielectric layer 3d is formed on these signal electrodes 6a to 6d.
Is placed. These dielectric layers 3a to 3d are laminated to form a laminate 2.

[0003] The signal electrodes 4a to 4d
And external electrodes 7a to which signal electrodes 6a to 6d are connected.
7h are formed. Further, two external electrodes 8 to which the ground electrode 5 is connected are formed on the outer surface of the laminate 2. The signal electrodes 4a, 6a are connected to the external electrodes 7a, 7e. Therefore, conduction is provided between the external electrodes 7a and 7e, and a capacitance is formed between the external electrodes 7a and 7e and the external electrode 8. Similarly, signal electrodes 4b and 6b are connected to external electrodes 7b and 7f, signal electrodes 4c and 6c are connected to external electrodes 7c and 7g, and signal electrodes 4d and 6d are connected to external electrodes 7d and 7h. You.

[0004] The laminated three-terminal capacitor array 1 is used, for example, as a noise filter. That is, by connecting the external electrode 8 to the ground potential and flowing a signal between the external electrodes 7a and 7e, the signal is included in the signal by the capacitance formed between the external electrodes 7a and 7e and the external electrode 8. Noise is removed. In the laminated three-terminal capacitor array 1, a plurality of such three-terminal capacitors are formed, so that noise of a plurality of signals can be removed by one chip.

As shown in FIG. 11, the laminated three-terminal capacitor array 1 has signal electrodes 4a to 4d formed on the same surface and signal electrodes 6a to 6d formed on another same surface. Therefore, a stray capacitance is generated between adjacent signal electrodes 4a to 4d. Similarly, the signal electrodes 6a to 6d
A stray capacitance is generated between adjacent ones. Due to this stray capacitance, when a signal flows through a plurality of three-terminal capacitors,
A signal flowing through the three-terminal capacitor is transmitted to another three-terminal capacitor, and so-called crosstalk occurs. In order to reduce the stray capacitance between such signal electrodes, as shown in FIG. 12, the signal electrodes 4a and 4c and the signal electrodes 4b and 4d are formed on different surfaces, and the signal electrodes 6a and 6c and the signal electrode 6b are formed. , 6d are formed on different surfaces. The ground electrodes 5 are formed between the surfaces on which the signal electrodes are formed.

In this laminated three-terminal capacitor array 1,
For example, since the ground electrode 5 is formed between the two signal electrodes 4a and 4b, these signal electrodes 4a and 4b
No stray capacitance occurs between them. Further, since the distance between the adjacent signal electrodes 4a and 4c in the same plane increases, the stray capacitance generated between the signal electrodes 4a and 4c decreases. The same applies to other signal electrodes. Since no stray capacitance is generated between the signal electrodes on both sides of the ground electrode and the distance between adjacent signal electrodes in the same plane is large, the generated stray capacitance is small. Therefore, in the multilayer three-terminal capacitor array 1 shown in FIG. 12, crosstalk can be reduced as compared with the one shown in FIG.

[0007]

However, with the demand for miniaturization of electronic components, miniaturization of multilayer three-terminal capacitor arrays has been promoted. In this case, the distance between the signal electrodes in the same plane decreases, the stray capacitance increases, and the crosstalk increases. Further, the signal electrodes on both sides of the ground electrode form a capacitance with the same ground electrode. Therefore, a signal may be transmitted between the signal electrodes on both sides of the ground electrode via the ground electrode, and crosstalk may still occur.

SUMMARY OF THE INVENTION Therefore, a main object of the present invention is to provide a laminated three-terminal capacitor array having a small size and a small crosstalk.

[0009]

According to the present invention, a plurality of dielectric layers, a plurality of signal electrodes formed on the dielectric layers, and an entire surface of the dielectric layer where no signal electrodes are formed are formed. In a dielectric layer including a ground electrode and a signal electrode formed thereon, only one signal electrode is formed on one dielectric layer, and a plurality of signal electrodes are provided between adjacent signal electrodes. The dielectric layers were laminated so that the ground electrodes were arranged to form a laminate, and external electrodes connected to the signal electrode and the ground electrode were formed on the outer surface of the laminate.
A multilayer three-terminal capacitor array, wherein adjacent signal
Poles do not have faces facing each other in the stacking direction
Is a stacked three-terminal capacitor array. The laminated three-terminal capacitor array odor Te, may be connected to a plurality of signal electrodes to the same external electrode.

Since only one signal electrode is formed on one dielectric layer and the ground electrode is arranged between the plurality of signal electrodes, no stray capacitance occurs between the plurality of signal electrodes. Therefore, crosstalk due to stray capacitance between signal electrodes can be reduced. Moreover, since only one signal electrode is formed on one dielectric layer, generation of stray capacitance between the signal electrodes can be prevented even if the size is reduced. In such a laminated three-terminal capacitor array,
If a plurality of ground electrodes are formed between signal electrodes, each signal electrode forms a capacitance with a different ground electrode, and crosstalk via the ground electrode can be reduced. Further, by connecting a plurality of signal electrodes to the same external electrode, the capacity can be increased, and at the same time, the cross-sectional area of the signal electrode of one three-terminal capacitor can be increased, and the current capacity can be increased.

The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

[0012]

FIG. 1 is a perspective view showing an example of a multilayer three-terminal capacitor array according to the present invention. The multilayer three-terminal capacitor array 10 includes a multilayer body 12. Laminate 1
2 includes a first dielectric layer 14, as shown in FIG.
On the first dielectric layer 14, a linear first signal electrode 16 extending in the width direction is formed. First signal electrode 16
Is at a portion near one end of the first dielectric layer 14,
It is formed so as to be substantially parallel to one end thereof. And
The first signal electrode 16 is formed so as to be exposed on both sides of the first dielectric layer 14 in the width direction.

On the first dielectric layer 14 on which the first signal electrode 16 is formed, a second dielectric layer 18 is laminated.
On the second dielectric layer 18, a ground electrode 20 is formed on almost the entire surface except for both sides where the first signal electrode 16 is exposed. Further, a third dielectric layer 22 is laminated on the ground electrode 20. A second signal electrode 24 is formed on the third dielectric layer 22 in parallel with the first signal electrode 16. The second signal electrode 24 is connected to the third dielectric layer 2
2 are formed so as to be exposed on both sides in the width direction. Then, the second signal electrode 24 is formed at a position shifted from the first signal electrode 16.

On the third dielectric layer 22 on which the second signal electrode 24 is formed, a fourth dielectric layer 26 is laminated.
On the fourth dielectric layer 26, a ground electrode 28 is formed on almost the entire surface except on both sides where the first and second signal electrodes 16 and 24 are exposed. Further, on the ground electrode 28, a fifth dielectric layer 30 is laminated. A third signal electrode 32 is formed on the fifth dielectric layer 30 in parallel with the first and second signal electrodes 16 and 24. The third signal electrode 32 is formed so as to be exposed on both sides of the fifth dielectric layer 30 in the width direction. And the third signal electrode 3
2 is formed at a position shifted from the first and second signal electrodes 16 and 24.

On the fifth dielectric layer 30 on which the third signal electrode 32 is formed, a sixth dielectric layer 34 is laminated.
On the sixth dielectric layer 34, a ground electrode 36 is formed on almost the entire surface except for both sides where the first, second, and third signal electrodes 16, 24, and 32 are exposed. Further, a seventh dielectric layer 38 is stacked on the ground electrode 36.
On the seventh dielectric layer 38, in parallel with the first, second and third signal electrodes 16, 24, 32, a fourth signal electrode 40
Is formed. The fourth signal electrode 40 is formed so as to be exposed on both sides of the seventh dielectric layer 38 in the width direction.
Further, the fourth signal electrode 40 includes the first, second, and third signal electrodes.
Are formed at positions displaced from the signal electrodes 16, 24, 32. On the seventh dielectric layer 38 on which the fourth signal electrode 40 is formed, an eighth dielectric layer 42 is laminated.

The signal electrodes 16, 24, 32,
External electrodes 44a,
44b, 44c, 44d and external electrodes 44e, 44
f, 44g and 44h are formed. One end of the first signal electrode 16 is connected to the external electrode 44a.
Is connected to the other end of the first signal electrode 16. One end of the second signal electrode 24 is connected to the external electrode 44b, and the other end of the second signal electrode 24 is connected to the external electrode 44f. One end of the third signal electrode 32 is connected to the external electrode 44c, and the third signal electrode 32 is connected to the external electrode 44g.
Are connected to each other. One end of the fourth signal electrode 40 is connected to the external electrode 44d, and the other end of the fourth signal electrode 40 is connected to the external electrode 44h.

Further, the external electrodes 44a-4
On the two side surfaces where 4h is not formed, another external electrode 46a, 46b is formed. These external electrodes 46
a, 46b have three ground electrodes 20, 28, 36
Is connected. As shown in FIG. 3, the inside of the multilayer three-terminal capacitor array 10 includes a first signal electrode 16 and a second signal electrode 16.
The signal electrodes 24, the third signal electrode 32, and the fourth signal electrode 40 are arranged in a step shape.
4, 32, 40, ground electrodes 20, 28, 36
Is arranged.

In this laminated three-terminal capacitor array 10, the external electrodes 46a and 46b are connected to the ground potential. Then, between the external electrodes 44a and 44e,
Signals flow between b and 44f, between the external electrodes 44c and 44g, and between the external electrodes 44d and 44h. Therefore,
As shown in FIG. 4, a signal flows through the signal electrodes 16, 24, 32, 40, and the signal electrodes 16, 24, 32, 4
0 and the ground electrodes 20, 28, 36 form a capacitance. Therefore, the external electrodes 44a, 44b, 4
When a signal is input to the external electrodes 44e, 4d, the noise contained therein is removed by the capacitance.
Signals without noise are output from 4f, 44g, and 44h.

In this laminated three-terminal capacitor array 10, only one signal electrode is formed on one dielectric layer, and a ground electrode is arranged between each signal electrode. That is, since the ground electrode always exists between the adjacent signal electrodes, no stray capacitance occurs between the signal electrodes. Therefore, even if the laminated three-terminal capacitor array 10 is miniaturized, a signal can be prevented from being transmitted from one signal electrode to another signal electrode due to a stray capacitance between the signal electrodes, and so-called crosstalk can be reduced. .

However, in the multilayer three-terminal capacitor array 10 shown in FIG. 2 and FIG.
And the second signal electrode 24 share the ground electrode 20,
The second signal electrode 24 and the third signal electrode 32 share the ground electrode 28, and the third signal electrode 32 and the fourth signal electrode 40 share the ground electrode 36. Therefore, it may not be possible to prevent crosstalk via these ground electrodes 20, 28, 36. Therefore, it is conceivable to form a plurality of ground electrodes between each signal electrode as shown in FIG.

In this laminated three-terminal capacitor array 10, two ground electrodes 20a and 20b are formed between the first signal electrode 16 and the second signal electrode 24. Similarly, the second signal electrode 24 and the third signal electrode 32
, Two ground electrodes 28 a and 28 b are formed, and between the third signal electrode 32 and the fourth signal electrode 40, two ground electrodes 36 a and 36 b are formed. And, these ground electrodes 20a, 20b, 2
8a, 28b, 36a, 36b are external electrodes 46a, 46
b, and the external electrodes 46a and 46b are connected to the ground potential.

Also in this laminated three-terminal capacitor array 10, since the ground electrode is formed between the signal electrodes, no stray capacitance occurs between the signal electrodes, and crosstalk between the signal electrodes can be reduced. . Further, since two ground electrodes are formed between the signal electrodes, and these ground electrodes have the same potential, crosstalk between the ground electrodes can be reduced.

To explain this, an equivalent circuit when two ground electrodes are formed between signal electrodes is shown in FIG. 6, and an equivalent circuit when one ground electrode is formed between signal electrodes is shown in FIG. Show. In these equivalent circuits, C
Reference numeral 1 denotes a capacitance formed between one signal electrode and a ground electrode, and C2 denotes a capacitance formed between another signal electrode and a ground electrode. Also, L1 and L
2 is a residual inductance of the ground electrode. Here, L1 is the inductance existing between the external electrode 46a or 46b and the signal electrode close thereto, and L2
Is the inductance of the ground electrode existing in the range of the interval between the two signal electrodes. Further, L0 is a residual inductance of an electrode of a circuit board on which the laminated three-terminal capacitor array 10 is mounted.

In FIG. 7, the ground electrode between the signal electrodes is 1
Therefore, the two capacitances C1 and C2 are connected by one inductance L2. On the other hand, in FIG. 6, since there are two ground electrodes between the signal electrodes,
Two capacitances C1 and C2 are connected by an inductance L1 present on two ground electrodes and an inductance L2 present on one ground electrode.

In the equivalent circuit shown in FIG. 7, the noise transmitted from the capacitance C2 to the ground electrode flows to the ground via the inductances L2, L1, L0, and is transmitted from the capacitance C1 to other signal electrodes. Absent. However, when the frequency of the noise increases, the impedance of the capacitance C1 decreases. When the frequency approaches the impedance of the inductance L1 + L0, the noise is easily transmitted to other signal electrodes via the capacitance C1, as indicated by arrows. . In contrast, in the equivalent circuit shown in FIG.
Since the capacitances C1 and C2 are not connected only by the inductance L2, the capacitance C1
Is small, the inductance L between the capacitance C1 and the inductance L0 of the circuit board is small.
As long as 1 is larger than L0, noise does not propagate to the capacitance C1 side as indicated by the arrow.

As described above, since only one signal electrode is formed on one dielectric layer and two ground electrodes are formed between the signal electrodes, crosstalk between the signal electrodes and the ground electrode are interposed. Crosstalk can be reduced. The number of ground electrodes between signal electrodes is
It goes without saying that not only two but also three or more ground electrodes may be formed.

In order to increase the current capacity of the signal electrode, a plurality of signal electrodes may be formed between input / output external electrodes as shown in FIG. Here, in addition to the multilayer structure of the multilayer three-terminal capacitor array shown in FIG.
4 are formed. Further, the ground electrodes 22a, 22
2b, 28a, 28b, 36a, 36b, and ground electrodes 56a, 56b, 58a, 58b, 60a, 6
0b, 62a and 62b are formed. Two of these ground electrodes are formed between each of the signal electrodes.

The signal electrodes 16 and 48 are formed at positions corresponding to each other, and are connected to the external electrodes 44a and 44e.
Similarly, the signal electrodes 24 and 50, the signal electrodes 32 and 52, and the signal electrodes 40 and 54 are formed at positions corresponding to each other, and the external electrodes 44b and 44f and the external electrode 44, respectively.
c, 44g and external electrodes 44d, 44h. In this laminated three-terminal capacitor array 10, for example, two signal electrodes 16, 4 are provided between external electrodes 44a, 44e.
8 is connected, the cross-sectional area of the signal electrode is twice as large as that of the stacked three-terminal capacitor array shown in FIG. 5 in which only one signal electrode 16 is connected. Therefore, the current capacity of the signal electrode between the external electrodes 44a and 44e increases, and a large current signal can flow.

Of course, the number of signal electrodes connected between the external electrodes may be three or more, and the number of signal electrodes connected between the external electrodes may be adjusted according to a desired current capacity. . In order to increase the number of signal electrodes between the external electrodes, the number of stacked dielectric layers on which the signal electrodes are formed may be increased, and by forming the ground electrode between each signal electrode, as described above, Crosstalk can be prevented. The current capacity of a three-terminal capacitor array in which one ground electrode is formed between signal electrodes can be increased by increasing the number of signal electrodes connected between external electrodes.

[0030]

According to the present invention, only one signal electrode is formed on one dielectric layer, and by forming a ground electrode between the signal electrodes, a floating capacitance is formed between the signal electrodes. No crosstalk occurs between the signal electrodes without generation. Therefore, the distance between the signal electrodes can be reduced, and the size of the laminated three-terminal capacitor array can be reduced. Further, by providing two or more ground electrodes between the signal electrodes, adjacent ground electrodes have the same potential, and crosstalk via the ground electrodes can be suppressed. In addition, one of three
By connecting a plurality of signal electrodes between the external electrodes forming the terminal capacitor, the current capacity can be increased, and a large current signal can flow.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a multilayer three-terminal capacitor array of the present invention.

FIG. 2 is an exploded perspective view showing a multilayer body of the multilayer three-terminal capacitor array shown in FIG.

FIG. 3 is an illustrative sectional view of the multilayer three-terminal capacitor array shown in FIG. 1;

FIG. 4 is an equivalent circuit diagram of the multilayer three-terminal capacitor array shown in FIG.

FIG. 5 is an illustrative sectional view showing another example of the multilayer three-terminal capacitor array of the present invention.

FIG. 6 is an equivalent circuit diagram showing a relationship between two three-terminal capacitors formed in the multilayer three-terminal capacitor array shown in FIG.

FIG. 7 is an equivalent circuit diagram illustrating a relationship between two three-terminal capacitors formed in the multilayer three-terminal capacitor array illustrated in FIG. 3;

FIG. 8 is an illustrative sectional view showing a modification of the multilayer three-terminal capacitor array shown in FIG. 5;

FIG. 9 is a perspective view showing an example of a conventional laminated three-terminal capacitor array.

FIG. 10 is an exploded perspective view of a multilayer body used in the conventional multilayer three-terminal capacitor array shown in FIG.

11 is an illustrative sectional view of the conventional multilayer three-terminal capacitor array shown in FIG.

12 is an illustrative sectional view showing a multilayer three-terminal capacitor array in which crosstalk of the multilayer three-terminal capacitor array shown in FIG. 11 is improved.

[Explanation of symbols]

 Reference Signs List 10 laminated three-terminal capacitor array 12 laminated body 14 first dielectric layer 16 first signal electrode 18 second dielectric layer 20 ground electrode 22 third dielectric layer 24 second signal electrode 26 fourth dielectric Body layer 28 Ground electrode 30 Fifth dielectric layer 32 Third signal electrode 34 Sixth dielectric layer 36 Ground electrode 38 Seventh dielectric layer 40 Fourth signal electrode 42 Eighth dielectric layer 44a to 44h External electrode 46a, 46b External electrode 48, 50, 52, 54 Signal electrode 56a, 56b, 58a, 58b Ground electrode 60a, 60b, 62a, 62b Ground electrode

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H01G 4/38 H01G 4/35

Claims (2)

(57) [Claims] 1. A laminate comprising: a plurality of dielectric layers; a plurality of signal electrodes formed on the dielectric layer; and a ground electrode formed on the entire surface of the dielectric layer where the signal electrodes are not formed. In the dielectric layer on which the signal electrodes are formed, only one signal electrode is formed on one dielectric layer, and a plurality of ground electrodes are provided between adjacent signal electrodes. A stacked three-terminal capacitor array in which the dielectric layers are stacked so as to be arranged to form a stacked body, and external electrodes connected to the signal electrode and the ground electrode are formed on the outer surface of the stacked body. And the adjacent signal electrodes face each other in the stacking direction.
A stacked three-terminal capacitor array arranged so as not to have a flat surface . 2. The multilayer three-terminal capacitor array according to claim 1, wherein a plurality of said signal electrodes are connected to the same external electrode.